CN209118161U - A kind of differential output constant-current source circuit - Google Patents
A kind of differential output constant-current source circuit Download PDFInfo
- Publication number
- CN209118161U CN209118161U CN201920053937.3U CN201920053937U CN209118161U CN 209118161 U CN209118161 U CN 209118161U CN 201920053937 U CN201920053937 U CN 201920053937U CN 209118161 U CN209118161 U CN 209118161U
- Authority
- CN
- China
- Prior art keywords
- current source
- constant
- current
- amplifier
- connect
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Landscapes
- Amplifiers (AREA)
Abstract
The utility model discloses a kind of differential output constant-current source circuits, including the first constant-current source, the second constant-current source, the first current detection module, the second current detection module and error amplifier；First constant-current source is connect with positive supply；First current detection module is connect with first constant-current source, error amplifier and external loading respectively；The error amplifier is connect with first constant-current source；Second constant-current source is connect with negative supply；Second current detection module is connect with second constant-current source, error amplifier and external loading respectively.A kind of differential output constant-current source circuit provided by the embodiment of the utility model does not change the original common-mode voltage over the ground of external loading, does not use isolated power supply, can be avoided common-mode noise problem.
Description
Technical field
The utility model embodiment is related to field of circuit technology more particularly to a kind of differential output constant-current source circuit.
Background technique
A floating constant current source is needed in CAN uniformity test equipment, and the end that constant current is loaded into CAN bus is provided
It holds on resistance, forms the differential voltage of an outside in CAN bus, CAN bus connects a tested CAN device, test equipment
Judge the response of CAN device when additional difference differential voltage in CAN bus, test equipment is sentenced according to the response condition of CAN device
Whether the tested CAN device that breaks is qualified.
CAN bus has 3 lines, is CAN_H, CAN_L and CAN_GND respectively.CAN_GND is the reference of CAN_H, CAN_L
Ground.Tested CAN device draws this 3 with line, and CAN_GND is connected with the ground of CAN uniformity test equipment.
Requirement to constant-current source is: entering in terms of from CAN bus to constant-current source, CAN_H is to CAN_GND, CAN_L to CAN_
High impedance and symmetrical is presented in GND, and the constant-current source of load does not change voltage of the CAN_H to CAN_GND, CAN_L to CAN_GND.
The prior art is by giving Single-end output constant current source power supply with isolated power supply, and constant-current source is completely isolated with CAN device.
The DAC output end powered using the same isolated power supply is connected to the control terminal of constant-current source, passes through optocoupler or other offer data
Constant current source current setting code is transferred to DAC number input terminal by the electronic device of isolation, so that the output electric current of constant-current source be arranged
Value, as shown in Figure 1.
However, when the prior art using isolated power supply to constant current source power supply, isolated power supply is by inverter circuit by direct current
Electricity becomes high-frequency alternating current, and by transformer coupled to secondary, secondary obtains floating straight with primary one be isolated through over commutation
When galvanic electricity source, due to all there is high-frequency alternating current in transformer primary and secondary, in primary and secondary there are a noise voltage, this voltage is logical
With crossing transformer secondary output, constant-current source, CAN bus, test equipment, primary constitute circuit, CAN_H to CAN_GND,
CAN_L produces noise voltage to CAN_GND, influences measurement accuracy.
On the other hand, transformer primary and secondary winding coiling on the same iron core, there are stray capacitance, constant currents between primary and secondary
Source output terminal is high impedance, it is assumed that constant-current source output connection CAN_H, then the anode or ground of CAN_L connection isolated power supply, isolation are electric
Source positive and negative anodes are then equivalent to one end that CAN_L is connected to stray capacitance, make to being exchange Low ESR between rectifier and secondary windings
It is asymmetric to the impedance of CAN_GND, CAN_L to CAN_GND at CAN_H.Even if being reduced altogether by dual shield primary and secondary winding
Mode noise, but stray capacitance can not be eliminated, it is unable to resolved impedance spectroscopy asymmetry problem.
Utility model content
The utility model provides a kind of differential output constant-current source circuit, so as to solve the deficiencies in the prior art.
To achieve the above objectives, the present invention provides the following technical solutions:
A kind of differential output constant-current source circuit, including the first constant-current source, the second constant-current source, the first current detection module,
Two current detection modules and error amplifier；
First constant-current source is connect with positive supply；First current detection module respectively with first constant-current source,
Error amplifier is connected with external loading；The error amplifier is connect with first constant-current source；Second constant-current source with
Negative supply connection；Second current detection module is connect with second constant-current source, error amplifier and external loading respectively.
Further, in the differential output constant-current source circuit, first constant-current source includes triode and divider resistance,
The emitter of the triode divider resistance of connecting is connected to the positive supply, the collector of the triode and described the
The connection of one current detection module, the base stage of the triode are connect with the error amplifier.
Further, in the differential output constant-current source circuit, first current detection module includes instrument amplifier
And current sense resistor, the current sense resistor is in parallel with the instrument amplifier, the positive input terminal of the instrument amplifier
It is connect with the collector of the triode, the negative input end of the instrument amplifier is connect with external loading, the instrument amplification
The output end of device is connect with the error amplifier.
Further, in the differential output constant-current source circuit, the error amplifier is made of two-stage calculation amplifier,
Output end one resistance of series connection for being parallel with the first order operational amplifier of a capacitor is connected to the second level for being parallel with a resistance
Negative input end one resistance of series connection of the negative input end of operational amplifier, the first order operational amplifier is connected to the instrument
The output end of amplifier, the positive input terminal of the first order operational amplifier is connect with second current detection module, described
The positive input terminal of second level operational amplifier is grounded, the output end of the second level operational amplifier and the base stage of the triode
Connection.
Further, in the differential output constant-current source circuit, second current detection module includes instrument amplifier
And current sense resistor, the current sense resistor is in parallel with the instrument amplifier, the negative input end of the instrument amplifier
It is connect with second constant-current source, the positive input terminal of the instrument amplifier is connect with external loading, the instrument amplifier
Output end is connect with the positive input terminal of the first order operational amplifier.
Further, in the differential output constant-current source circuit, second constant-current source includes triode, operational amplifier
And divider resistance, the emitter series connection divider resistance of the triode are connected to the negative supply, the collection of the triode
Electrode is connect with the negative input end of the instrument amplifier, and the output end of the base stage of the triode and the operational amplifier connects
It connects, the positive input terminal of the operational amplifier is connected to the control voltage of setting output electric current, and bearing for the operational amplifier is defeated
Enter end to be connected between the emitter of the triode and the divider resistance.
Further, in the differential output constant-current source circuit, the external loading includes tested CAN device and CAN mono-
Cause property measuring device；
The tested CAN device has tri- terminals of CAN_H, CAN_L and CAN_GND, CAN_GND ground connection, CAN_H and CAN_
Terminal resistance is connected between L；
Two input terminals of the CAN coherence measurement equipment are separately connected CAN_H, CAN_L, one is with reference to termination
Ground, the interior CAN coherence measurement equipment includes that one test resistance of common-mode current source connection for generating common-mode voltage arrives it
In an input terminal, common-mode current source other end ground connection.
A kind of differential output constant-current source circuit provided by the embodiment of the utility model, it is original over the ground not change external loading
Common-mode voltage does not use isolated power supply, can be avoided common-mode noise problem.
Detailed description of the invention
In order to illustrate the embodiment of the utility model or the technical proposal in the existing technology more clearly, below will be to embodiment
Or attached drawing needed to be used in the description of the prior art is briefly described, it should be apparent that, the accompanying drawings in the following description is only
It is some embodiments of the utility model, for those of ordinary skill in the art, before not making the creative labor property
It puts, can also be obtained according to these attached drawings other attached drawings.
Fig. 1 is the electrical block diagram that the utility model prior art provides.
Fig. 2 is the structural schematic diagram for the differential output constant-current source circuit that the utility model embodiment one provides；
Fig. 3 is the concrete structure schematic diagram for the differential output constant-current source circuit that the utility model embodiment one provides.
Appended drawing reference:
First constant-current source 100, the second constant-current source 200, the first current detection module 300, the second current detection module 400,
Error amplifier 500.
Specific embodiment
The utility model is described in further detail with reference to the accompanying drawings and examples.It is understood that herein
Described specific embodiment is used only for explaining the utility model, rather than the restriction to the utility model.It further needs exist for
It is bright, part relevant to the utility model is illustrated only for ease of description, in attached drawing rather than entire infrastructure.
Embodiment one
Attached drawing 2 is please referred to, is that a kind of structure for differential output constant-current source circuit that the utility model embodiment one provides is shown
It is intended to, which specifically includes:
First constant-current source 100, the second constant-current source 200, the first current detection module 300,400 and of the second current detection module
Error amplification 500；
First constant-current source 100 is connect with positive supply；First current detection module 300 is permanent with described first respectively
Stream source 100, error amplification 500 are connected with external loading；The error amplification 500 is connect with first constant-current source 100；It is described
Second constant-current source 200 is connect with negative supply；Second current detection module 400 respectively with second constant-current source 200, error
Amplification 500 is connected with external loading.
Preferably, the external loading includes tested CAN device and CAN coherence measurement equipment；
The tested CAN device has tri- terminals of CAN_H, CAN_L and CAN_GND, CAN_GND ground connection, CAN_H and CAN_
Terminal resistance Rdiff is connected between L；
Two input terminals of the CAN coherence measurement equipment are separately connected CAN_H, CAN_L, one is with reference to termination
Ground, the interior CAN coherence measurement equipment includes that one test resistance of common-mode current source connection for generating common-mode voltage arrives it
In an input terminal, common-mode current source other end ground connection.
Specifically, the first constant-current source 100 is that source goes out constant-current source, 1 foot is connected to positive supply, and 3 feet are current output terminals, stream
The electric current of 3 feet is controlled by the voltage of 2 feet out, and the electric current of the smaller then 3 feet outflow of 2 foot voltage-to-grounds is bigger.3 foot electric currents flow into first
Current detection module is flowed out from 6 feet, and the electric current that the detection of the first current detection module is flowed through generates one and be proportional in 5 feet to be flowed through
The voltage output signal of electric current, the signal are referenced to ground.Second constant-current source 200 is to absorb constant-current source, and 10 feet are electric current stream
Enter end, 12 feet connect negative supply, and 11 feet are control voltage input ends, and the voltage of 11 feet the big, and the electric current for flowing through 10 feet is bigger.The
In two current detection modules, electric current flows into the outflow of 9 feet from 7 feet, subsequently into 10 feet of the second constant-current source 200, the inspection of the second electric current
8 feet for surveying module generate one and are proportional to the voltage signal output for flowing through electric current, which is referenced to ground.The inspection of second electric current
An input terminal 14 for surveying the output signal connection error amplification 500 of module is used as reference signal, the first current detection module
Output signal is connected to another input terminal 13 of error amplification 500, and error amplification 500 compares the size of two input voltages simultaneously
It generates a voltage signal for being proportional to two input voltage differences to export in 15 feet, which is sent to the first constant-current source 100
2 feet.
The 6 feet output electric current of first current detection module 300 flows through Rdiff, in 7 feet of the second current detection module 400
It returns.
It should be noted that the first constant-current source 100 (source goes out constant-current source) and the second constant-current source 200 (absorbing constant-current source) which
It is a to be arbitrary as setting electric current, it can be the second constant-current source 200 and make setting load current, the first constant-current source 100 follows, also
It can be the first constant-current source 100 and make setting load current, the second constant-current source 200 follows.Fig. 2 is one of controlling party
Formula, another way are then: 2 feet are changed to meet electric current setting voltage Vc, and 11 feet instead connect to 15 feet, and 5 feet instead connect to 14
Foot, 8 feet instead connect to 13 feet.
Based on Fig. 2 disclosure, Fig. 3 is a specific embodiment provided by the utility model, worked for illustrating
Journey.Specifically, first constant-current source 100 includes triode and divider resistance, described point of the emitter series connection of the triode
Piezoresistance is connected to the positive supply, and the collector of the triode is connect with first current detection module 300, and described three
The base stage of pole pipe is connect with error amplification 500.
First current detection module 300 includes instrument amplifier and current sense resistor, the current sense resistor
In parallel with the instrument amplifier, the positive input terminal of the instrument amplifier is connect with the collector of the triode, the instrument
The negative input end of table amplifier is connect with external loading, and the output end of the instrument amplifier is connect with error amplification 500.
The error amplification 500 is made of two-stage calculation amplifier, is parallel with the first order operational amplifier of a capacitor
Output end one resistance of series connection is connected to the negative input end for being parallel with the second level operational amplifier of a resistance, the first order fortune
Negative input end one resistance of series connection for calculating amplifier is connected to the output end of the instrument amplifier, the first order operation amplifier
The positive input terminal of device is connect with second current detection module 400, the positive input terminal ground connection of the second level operational amplifier,
The output end of the second level operational amplifier is connect with the base stage of the triode.
Second current detection module includes instrument amplifier and current sense resistor, the current sense resistor and institute
Instrument amplifier parallel connection is stated, the negative input end of the instrument amplifier is connect with second constant-current source 200, the instrument amplification
The positive input terminal of device is connect with external loading, and the output end of the instrument amplifier is just defeated with the first order operational amplifier
Enter end connection.
Second constant-current source 200 includes triode, operational amplifier and divider resistance, the emitter string of the triode
Join the divider resistance and is connected to the negative supply, the negative input end company of the collector of the triode and the instrument amplifier
It connects, the base stage of the triode is connect with the output end of the operational amplifier, the positive input terminal connection of the operational amplifier
To the control voltage of setting output electric current, the negative input end of the operational amplifier is connected to emitter and the institute of the triode
It states between divider resistance.
Illustratively, the triode in Fig. 3 also may be replaced by field-effect tube.
With Fig. 3 for embodiment illustrate working principle.A41, Q2, R4 constitute a constant-current source, and A41 is an amplifier.Vc
It is the control voltage to negative supply Vee reference, is that the pressure drop on R4 is equal to control voltage Vc by the negative feedback of amplifier,
The required electric current for flowing through R4 can be obtained for given Vc, because the common emitter current amplification factor hfe of triode is much larger than
1, therefore the electric current for flowing into 10 feet is believed that the electric current for being equal to and flowing through R4.The electric current that Q2 is generated flows through R3, and instrument amplifier A31 is put
Pressure drop on big R3, A31 export the voltage signal referred to over the ground in 8 feet, which is proportional to the electric current for flowing through R3,8 foot voltages
It is input to the non-inverting input terminal of amplifier A51.Q1 exports an electric current in 3 feet under the control of 2 foot voltages, which flows through R2, A21
The pressure drop for amplifying R2 is proportional to the voltage signal for flowing through R2 electric current at the output of 5 feet one, which refers to over the ground, this
Voltage signal is connected to A51 reverse input end by resistance R5.
A51, A52, C1, R5, R6, R7 constitute error amplifier.It is reference with the voltage of 14 foot of in-phase end, if flowing through R2's
Electric current decline, then A21 output voltage declines, and 13 foot voltages are lower than 14 foot voltages, then the difference is amplified by the open-loop gain of A51,
A51 output voltage rises at this time, becomes declining in the output of 15 feet by A52 phase inverter, declines base stage (2 foot) voltage of Q1,
Q1 base current increases, so Q1 collector current increases, R2 pressure drop rise, A21 output rises, and 13 foot output voltages rise,
To inhibit to flow through the electric current decline of R2, this is a negative feedback process.
If the electric current for flowing through R2 rises, A21 output voltage rises, and 13 foot voltages are higher than 14 foot voltages, then the difference quilt
The open-loop gain of A51 is amplified, and A51 output voltage declines at this time, is become rising in the output of 15 feet by A52 phase inverter, is made Q1's
Base stage (2 foot) voltage rises, and Q1 base current is reduced, so Q1 collector current is reduced, R2 pressure drop decline, A21 output decline,
The decline of 13 foot output voltages, so that the electric current for flowing through R2 be inhibited to rise, this is a negative feedback process.
If the voltage amplification factor of A21 is K21, the voltage amplification factor of A31 is K31.Particularly when following relationship at
Immediately:
K21 × R2=K31 × R3；
Then maintain the electric current for flowing through R2 equal to the electric current for flowing through R3 by feedback effect.
The effect of resistance R5 and capacitor C1 is that it is made not enter feedback control loop to guarantee loop stability to high frequency signal attenuation.
Due to the error of electronic component, the electric current for flowing through R2 is not exactly equal to flow through the electric current of R3, source current and absorption
The earth impedance that difference between currents flow through external circuit generates a common-mode voltage over the ground, but when the precision by control element can be with
The common-mode voltage over the ground for generating difference between currents is small to negligible degree.For example: set the voltage gain of A21 and A31
It is 1, test macro needs the electric current of 20mA, and R2, R3 resistance value are 100 Ω and select the precision-matched network electricity being packaged together
Resistance.Current technology can be easy to get the resistive element that resistance value matching degree is better than 0.01%, therefore after circuit stability, by electricity
Resistance mismatches the current error generated are as follows:
ΔI1=20mA × 0.01%=2 μ A；
Current instrument amplifier offset voltage is better than 50 μ V, and offset voltage is better than 10 μ V, and the influence of offset voltage can
Think that 14 foot voltages are equal to 20mA electric current and flow through pressure drop on R3, and 13 foot voltages are that 20mA flows through the voltage of R2 and adds again
Upper offset voltage, and negative feedback makes 13 foot voltages be equal to 14 foot voltages, so electric current on R2 is by less offset voltage
Divided by the electric current of R2 resistance value.Offset voltage has just and has negative, considers that all offset voltages of worst case are superimposed in the same direction, A21 and A31's
Voltage gain is 1, then the current deviation generated by offset voltage are as follows:
Above two parts offset current is superimposed then in the same direction as 3.1 μ A under worst case.In CAN uniformity test equipment
Diff is 60 Ω, and one is 1k Ω to ground resistance Rt, then offset current flows through the voltage-to-ground of this two resistance generation are as follows:
Δ V=(Δ I1+ΔI2) (1000+60)=3.286mV；
And the power supply for the generation CAN bus common-mode voltage that Rt is connected, the power supply need to be arranged CAN bus common-mode voltage
For -2V or+7V, it is seen that the common-mode voltage deviation that current deviation generates 3.286mV is very little, in CAN uniformity test equipment
In can be ignored.
A kind of differential output constant-current source circuit provided by the embodiment of the utility model, it is original over the ground not change external loading
Common-mode voltage does not use isolated power supply, can be avoided common-mode noise problem.
The above, above embodiments are only to illustrate the technical solution of the utility model, rather than its limitations；Although ginseng
The utility model is described in detail according to previous embodiment, those skilled in the art should understand that: it is still
It is possible to modify the technical solutions described in the foregoing embodiments, or part of technical characteristic is equally replaced
It changes；And these are modified or replaceed, various embodiments of the utility model technical solution that it does not separate the essence of the corresponding technical solution
Spirit and scope.
Claims (7)
1. a kind of differential output constant-current source circuit, which is characterized in that including the first constant-current source, the second constant-current source, the inspection of the first electric current
Survey module, the second current detection module and error amplifier；
First constant-current source is connect with positive supply；First current detection module respectively with first constant-current source, error
Amplifier is connected with external loading；The error amplifier is connect with first constant-current source；Second constant-current source and negative electricity
Source connection；Second current detection module is connect with second constant-current source, error amplifier and external loading respectively.
2. differential output constant-current source circuit according to claim 1, which is characterized in that first constant-current source includes three poles
The emitter series connection divider resistance of pipe and divider resistance, the triode is connected to the positive supply, the triode
Collector is connect with first current detection module, and the base stage of the triode is connect with the error amplifier.
3. differential output constant-current source circuit according to claim 2, which is characterized in that the first current detection module packet
Instrument amplifier and current sense resistor are included, the current sense resistor is in parallel with the instrument amplifier, the instrument amplification
The positive input terminal of device is connect with the collector of the triode, and the negative input end of the instrument amplifier is connect with external loading,
The output end of the instrument amplifier is connect with the error amplifier.
4. differential output constant-current source circuit according to claim 3, which is characterized in that the error amplifier is transported by two-stage
Amplifier composition is calculated, output end one resistance of series connection for being parallel with the first order operational amplifier of a capacitor, which is connected to, is parallel with one
Negative input end one resistance of series connection of the negative input end of the second level operational amplifier of resistance, the first order operational amplifier connects
It is connected to the output end of the instrument amplifier, the positive input terminal of the first order operational amplifier and the second current detecting mould
Block connection, the second level operational amplifier positive input terminal ground connection, the output end of the second level operational amplifier with it is described
The base stage of triode connects.
5. differential output constant-current source circuit according to claim 4, which is characterized in that the second current detection module packet
Instrument amplifier and current sense resistor are included, the current sense resistor is in parallel with the instrument amplifier, the instrument amplification
The negative input end of device is connect with second constant-current source, and the positive input terminal of the instrument amplifier is connect with external loading, described
The output end of instrument amplifier is connect with the positive input terminal of the first order operational amplifier.
6. differential output constant-current source circuit according to claim 5, which is characterized in that second constant-current source includes three poles
The emitter series connection divider resistance of pipe, operational amplifier and divider resistance, the triode is connected to the negative supply, institute
The collector for stating triode is connect with the negative input end of the instrument amplifier, the base stage of the triode and the operation amplifier
The output end of device connects, and the positive input terminal of the operational amplifier is connected to the control voltage of setting output electric current, the operation
The negative input end of amplifier is connected between the emitter of the triode and the divider resistance.
7. differential output constant-current source circuit according to claim 4, which is characterized in that the external loading includes tested
CAN device and CAN coherence measurement equipment；
The tested CAN device has tri- terminals of CAN_H, CAN_L and CAN_GND, CAN_GND ground connection, between CAN_H and CAN_L
It is connected with terminal resistance；
Two input terminals of the CAN coherence measurement equipment are separately connected CAN_H, CAN_L, one reference end ground connection, institute
State include in CAN coherence measurement equipment a generation common-mode voltage common-mode current source connect a test resistance to one of them
Input terminal, the common-mode current source other end ground connection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920053937.3U CN209118161U (en) | 2019-01-14 | 2019-01-14 | A kind of differential output constant-current source circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920053937.3U CN209118161U (en) | 2019-01-14 | 2019-01-14 | A kind of differential output constant-current source circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN209118161U true CN209118161U (en) | 2019-07-16 |
Family
ID=67209311
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201920053937.3U Active CN209118161U (en) | 2019-01-14 | 2019-01-14 | A kind of differential output constant-current source circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN209118161U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113741272A (en) * | 2021-09-01 | 2021-12-03 | 上海节卡机器人科技有限公司 | CAN bus communication system |
-
2019
- 2019-01-14 CN CN201920053937.3U patent/CN209118161U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113741272A (en) * | 2021-09-01 | 2021-12-03 | 上海节卡机器人科技有限公司 | CAN bus communication system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105406824B (en) | Common mode feedback circuit, corresponding signal processing circuit and method | |
| CN101667046B (en) | Low-voltage difference voltage adjuster | |
| CN102680851B (en) | Current leakage detecting method and current leakage detecting device | |
| CN203882224U (en) | Program-controlled constant-current source circuit | |
| CN107290581B (en) | Current detection circuit of switch circuit and switch circuit | |
| CN105811926B (en) | A kind of ring oscillator circuit of included temperature and process corner calibration | |
| CN103592490A (en) | High-accuracy electronic compensated current transformer | |
| CN103777047B (en) | Source of resistance range adjustment equipment and method | |
| US11621683B2 (en) | Current sensing circuitry | |
| CN104374979A (en) | Digital alternating current resistance electrical bridge | |
| CN110275104A (en) | A kind of weak current measuring device and measuring method of ATE system | |
| CN209118161U (en) | A kind of differential output constant-current source circuit | |
| CN107478279A (en) | Electromagnetic flowmeter and its excitation voltage regulation method | |
| US10348249B2 (en) | Method for load measurement in switching amplifiers, corresponding device and amplifier | |
| CN104950976B (en) | Voltage stabilizing circuit based on slew rate increasing | |
| CN101609345B (en) | Linear voltage regulator | |
| CN102590632A (en) | Insulation resistance test circuit for circuit board | |
| CN209979728U (en) | Bidirectional current detection circuit | |
| CN103838288A (en) | Direct-current regulated power supply | |
| CN108957100A (en) | A kind of current detection means | |
| CN105652140A (en) | Leakage current detection circuit | |
| CN114355020A (en) | Flow divider | |
| CN103279163A (en) | High-power-voltage-rejection-rate capacitor-free low-voltage-difference voltage regulator | |
| CN208537614U (en) | Current detection means | |
| CN212134792U (en) | Balanced symmetrical sampling circuit of direct current electric meter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20220811 Address after: Room 304, 3rd Floor, No. 43, Sicheng Road, Tianhe District, Guangzhou City, Guangdong Province, 510000 Patentee after: Guangzhou Zhiyuan Instrument Co., Ltd. Address before: 510000 room 517, 1023 Gaopu Road, Tianhe Software Park, Tianhe District, Guangzhou City, Guangdong Province Patentee before: GUANGZHOU ZHIYUAN ELECTRONICS Co.,Ltd. |
|
| TR01 | Transfer of patent right |